The proposed research is designed to study the changes in migratory, proliferative and differentiative patterns of equatorial zone cells of frog and mouse lens epithelium after a penetrating injury to the anterior capsule of the lens. Autoradiographic techniques will be used to follow the proliferative zone cells in their normal progression into the meridional rows and lens bow and the effect of injury on this progression will be determined. Furthermore, the contribution of the Go (injury-reserve) cell population to the resulting defects in lens fiber differentiation and posterior subcapsular epithelialization will be followed. Alterations in the fine structure of meridional row and bow cells will be studied with the electron microscope, and the changes correlated with differentiative defects associated with injury-induced cataract. The effect on proliferation of normal equatorial zone cells of changing the tension on the lens capsule will be investigated using autoradiography. Appropriate autonomic drugs will be used to change the tension of the zonular fibers on the lens. Alternatively, enzymatic dissolution of the capsule and zonular fibers will be used to release the tension on the epithelium.